MOSUL, Iraq — She survived the first stone that struck her, then the second.

One of the Islamic State group's fighters bent down and pressed his fingers to the side of her neck to check her pulse.

As her horrified neighbors watched, extremists threw a third stone at the young woman, who was accused of adultery. That one killed her.

It was, for those who witnessed it, the cruelest moment in Mosul's descent into fear, hunger and isolation under 2 ½ years of IS rule. Before the militants' takeover, Iraq's second-largest city was arguably the most multicultural place in the country, with a Sunni Muslim Arab majority but also thriving communities of Kurds, Shiites, Christians and Yazidis. Together, they had created Mosul's distinct identity, with its own cuisine, intellectual life and economy.

But the Islamic State group turned Mosul into a place of literal and spiritual darkness.

It began with promises of order and of a religious utopia that appealed to some. But over time, the militants turned crueler, the economy crumbled under the weight of war and shortages set in. Those who resisted watched neighbors who joined IS turn prosperous and vindictive. Parents feared for the brainwashing of their children. By the end, as Iraqi troops besieged Mosul, the militants hanged suspected spies from lampposts, and residents were cut off from the world.

The woman's killing in Mosul's Samah district shook to the core those in the crowd who were forced to watch.

Several witnesses described to The Associated Press how the woman and her alleged lover were paraded blindfolded through the streets. The militants summoned everyone they could find to watch. It was in August, after the militants had lost strongholds in other parts of Iraq and Syria, prompting them to heighten their repression.

"'Still not dead,'" Samira Hamid recalled the militant pronouncing after he checked the woman's pulse, before the lethal blow to her head. The man accused of being her lover was flogged 150 times and forced to go to Syria to fight in IS ranks.

Another witness, Sarmad Raad, found recalling the killing nearly unbearable.

"I shut down," the 26-year-old said, "I just lost my mind."

The AP interviewed dozens of residents who have left Mosul since Iraqi troops began retaking outlying districts last month. They described life in a city that has been virtually sealed off from the outside under the rule of the Islamic State group. They spoke from Mosul's edges and from the refugee camps that are their homes for the foreseeable future, even as smoke rose and artillery boomed from nearby front lines.

For many among Mosul's Sunni Arabs, rule by the Sunni militants of IS initially seemed a respite from what they considered the heavy hand of Iraq's Shiite-led central government in Baghdad.

As Iraqi soldiers vanished in those first few weeks, people were simply happy to see hated security checkpoints pulled down and traffic moving smoothly along streets lined with low, pale buildings. Sunni insurgents have long been active in Mosul, and Baghdad's clampdowns against them usually only fueled residents' distrust.

But even as families strolled in the parks and shops stayed open, signs emerged that this group of fighters was unlike past insurgents who had worked strictly underground. They were staying put: Trucks began hauling office furniture to various government buildings, according to a blog called "Mosul Eye," written by a resident who took on the role of city historian.

Several weeks later, the group declared its "caliphate" stretching across its territory in Syria and Iraq.

Within a month, the homes of Christians and other minorities were tagged with official stickers — for "statistical purposes," IS officials said, according to Mosul Eye. Christians and Shiites soon fled, leaving their marked homes and belongings behind.

Kurds were soon targeted as well.

"If you turned in a Kurdish family, they gave you a car," said Hassan Ali Mustapha, a retired prison guard. He said he moved into a home deserted by a Kurdish family, after the family asked him through a mutual friend to do so to keep Islamic State from taking it over.

Mustapha walked with a heavy limp through the camp that is his family's new home. They made their escape from Mosul first on foot and then by Iraqi government truck.

The group imposed the extreme, severe vision of Islamic law across its zone of control. Dress was strictly regulated, and clothes manufacturers were told to report to Islamic State offices to receive the acceptable measurements. Women were required to hide their faces and don black down to their fingertips. The fine for violations — even as small as the wrong kind of stocking — was 25,000 dinars, around 20 dollars. Repeat offenders got lashes.

There was another, widely feared punishment as well: The women's brigade of religious enforcers used a metal-toothed device to deliver vicious, deep "bites" on women they deemed as dressing improperly, according to two women.

Punishments were often public, and in a central square the group printed broadsheets proclaiming how it would respond to disobedience. In one case, according to a witness, there was a gleeful description of "criminals" being shoved into a commercial oven to roast to death.

The militants took a cut of all business through fees, fines or taxes. Even roadside hawkers had to pay IS according to the size of the sheet on the ground where they displayed their wares — 15,000 dinar ($12) per square meter. As they described indignities piling up, the camp residents dragged their feet in the dust to show just how small a space could be taxed.

Residents learned to keep a mental tally of all the different rules — and find ways to dissent.

The most symbolic was the widespread refusal to send children to the schools, which the extremists took over.

Mosul prides itself on an ancient history of knowledge. Near the center of the city are the ruins of the city of Nineveh where stone tablets more than 3,000 years old were discovered in a library, inscribed with the Mesopotamian epic of Gilgamesh, considered humanity's oldest surviving work of literature.

But in the IS schools, lessons were about guns and warplanes. Mathematics courses couldn't use a plus symbol because it resembled a Christian cross. Mosul's biggest libraries were ransacked over a number of weeks, beginning in late 2014, and the extremists set up bonfires to torch books on science and culture, according to accounts at the time.

Though IS threatened flogging and even death as punishments for absenteeism, students and teachers alike stayed away from the university, according to Mosul Eye.

Schools once free to everyone now involved fees that few could afford without a steady paycheck. By mid-2014, steady income came only from joining the Islamic State group. Many dismissed entirely the thought of paying their dwindling cash for a worthless education.

"So we didn't send them to school," said Khodriya Ahmed, a mother of 12 from the outlying neighborhood of Gogjali. "For two or three years, Daesh only educated their own children," she said, using the Arabic acronym for the group.

Hussam Ghareeb, a former soldier, also refused to send his children to IS-run schools.

He is living in a camp with his family, including his 6-year-old son Omar.

"God willing, you will be a doctor and help those who are hurt. Yes, son?" he asked, turning to the boy. Omar has yet to set foot in a classroom.

The group's propaganda insisted all was fine in the city. John Cantlie, a British journalist held hostage by the Islamic State group for four years, has made periodic appearances in videos filmed in Mosul, showing a market, an efficient IS motorcycle police force and a city continuing to function despite the threat of airstrikes from the Iraqi military and the U.S.-led coalition.

Members of the actual police force, meanwhile, had either been killed or gone into hiding as IS hunted down policemen or soldiers to eliminate the group of people best able to fight against them.

Oday Mustapha Suleiman, a former soldier, knew of two police officers killed by militants, as well as his brother. Suleiman himself spent most of his time inside his house for fear of being caught.

"They drove through the streets with a microphone, calling our names," he said. "For 10 days I hid, just pacing between my room and the front door because they wanted to cut off my head."

Azhar Yonas, a small, nervous man who fingered his prayer beads as he spoke, said his name was on an IS list of police officers so he went into hiding. Yonas estimated that a third of the 30,000 strong force was killed — tossed into a natural pit outside the city believed to hold thousands of bodies.

"They said they put them in the hole so they would not make the land unclean," Yonas said.

His youngest child was born July 3, 2014, a day before IS leader Abu Bakr al-Baghdadi mounted a dais in a Mosul mosque and gave a sermon demanding Muslims obey him as the newly declared "caliph."

Yonas' wife gave birth at the hospital without him. He did not dare join her.

The family skipped from relative to relative an estimated 100 times in 2½ years.

"Iraqis have big families," he said with a wry smile.

The city's economy suffered a string of blows. The Baghdad government cut off the flow of money it had been paying civil servants, and airstrikes cut into Islamic State's oil revenue and cash reserves. The infrastructure and services initially provided by the group broke down. Electricity cuts forced people to rely on oil lamps. Communications were cut off, although people still managed to make periodic, hushed calls to Alghan FM, a radio station founded by an exiled Mosul resident that has become a sounding board to those trapped in the city.

"Four months ago, satellite television went down. Six months ago, it was the internet," said the station's founder, who asked to be identified only by his first name, Mohammed, for his safety. IS "wanted people to be isolated completely."

IS enforcers cowed entire neighborhoods by forcing people to watch as they hacked off hands and lashed, beheaded or stoned offenders.

Hamid, one of the residents of the Samah neighborhood who witnessed the stoning, said her 39-year-old son suffers from severe psychological problems and ran afoul of Islamic State when he wandered from home one evening. They accused him of being drunk, clubbed him with a gun and took him away. In detention, they beat him more. Finally the family found out where he was being held and brought him home.

"Only his eyes were untouched. Everything else was bruised. And he became like a parrot, just repeating what we would say," she said.

Residents said IS fighters herded people into Mosul's central market nearly every week for public punishments. "They forced all of us to watch," said Raad, the 26-year-old, speaking in the Hassan Sham camp midway between Mosul and Irbil where he and many of his neighbors have ended up.

With the militants digging in as they lost territory elsewhere, Mosul's residents saw food supplies dwindle until onions and bread were all that was left. Prices that had been kept stable began to spiral. With food in short supply and jobs even scarcer, people started selling anything of value to anyone willing to buy.

Khodr Ahmed sold his car for $400 dollars. But as that money ran out, he sent his young boys Bashir and Mushal out to hunt for scrap metal.

As they scrounged, 9-year-old Bashir picked up what turned out to be an abandoned IS explosive. It blew off his hand and gouged a hole in his 10-year-old brother's shin.

"Poverty and hunger caused all of this," said Ahmed. And the poverty and hunger, he said, were caused by IS. "For them, they were living the good life. They had food to eat, but because we did not join, there was nothing for us."

Their neighbor was among those to reap the rewards of joining, the Ahmeds said. That family got a car and never wanted for food or electricity. But Khodriya, Ahmed's wife, said her refusal to fully accept IS rules for women earned her a death threat from the same neighbor — one he never had the chance to carry out.

In recent weeks, to further seal off Mosul's people from the world outside, Islamic State took to hanging people from street lights in residential neighborhoods, according to two men who fled Mosul, speaking on condition they not be named to protect their families. Most of the dead were caught using mobile phones, an act considered spying.

Still, people within Mosul find ways to communicate, if only briefly.

Saif, a man from the Zahra neighborhood, said his family inside the city managed to send quick texts to say they are safe. He spoke using only his first name to protect his relatives.

Mustapha, the former prison guard, was among those to keep his cell phone. He wrapped it in plastic and buried it in the garden, making only brief phone calls. One of his sons lives in Irbil. They have not seen each other since IS took over, although the two cities were, in better days, just an hour apart by car.

Mustapha now is unsure he would ever want to return home.

"Mosul is like a forest with hidden monsters," he said, but he knows everyone who joined the Islamic State. "I can remember everything."